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2 Polish Journal of Environmental Studies

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Evaluation of forest fire risk with GIS

100%

Sivrikaya F. , Saglam B. , Akay A. E. , Bozali N.

Polish Journal of Environmental Studies

2014

tom 23

nr 1

This paper uses GIS to describe and evaluate forest fire risk considering the most important factors affecting fire behavior at fine scales. The study was implemented in Yeşilova Forestry Enterprise in the Mediterranean city of Kahramanmaraş, Turkey. To determine an overall fire risk index for the study area, fire risk rating (extreme, high, moderate, or low) was assigned to decision variables (i.e. species composition, stand development stage, stand crown closure, slope, insolation, settlements, and roads) according to their risk potentials. Additionally, the visibility analysis of fire towers was carried out for monitoring of forests in the case study area. Finally, visibility analysis and a forest fire risk map were evaluated together for determining the efficiency of fire towers. Results indicated that more than half of the total forested area (65.7%) was classified as low category in the fire risk map. According to visibility analysis, the existing fire tower was able to monitor only 37% of forest areas; therefore, it was essential to consider new fire towers for monitoring the overall study area. After locating a potential new fire tower in the study area, it was found that about 71.8% of the area was with the visible zones of two fire towers.

Spatial and temporal changes in forest cover in Turkey's Artvin Forest, 1972-2002

88%

Keles S. , Sivrikaya F. , Cakir G. , Baskent E. Z. , Kose S.

tom 17

nr 4

491-501

This study analyses the spatial and temporal pattern of land use/forest cover change in the Artvin Forest Planning Unit (AFPU) surrounding the city of Artvin, Turkey. To assess the spatiotemporal changes in forest ecosystem patterns during 1972–2002, we evaluated forest stand maps of 1972, 1985 and 2002 using Geographic Information Systems (GIS). The results showed that the total forested areas decreased from 4617 ha (88.4% of the study area) in 1972 to 4167 ha (79.8%) in 2002, with a considerable net decrease of 450 ha. 198 ha forest openings changed into settlements and agriculture during the first period (1972-1985). 158 ha degraded forest areas changed into settlements and agriculture during the second period (1985-2002). The population of Artvin increased two times over 30 years and high variability in land use/forest cover changes during the study period was reported. In terms of spatial configuration, as a result of unplanned exploitation, settlement, dam and road construction, insect outbreaks on spruce stands, conversion and over utilization, many natural ecosystems were fragmented into small pieces in the AFPU and the total number of forest fragments rapidly increased from 108 to 202. Substantial increase in the number of patches and decrease in the average patch sizes between 1972 and 2002 indicated irregular land use and forest structure, and also suggested that human interventions had produced irregular land cover types.